Display system and method for driving same between normal mode and panel self-refresh (PSR) mode

Abstract

A display system includes a graphic processor and a display apparatus. The graphic processor supplies a first image signal and a first synchronization signal. The display apparatus is driven in a normal mode in which a first image is displayed, during a first period, based on the first image signal and the first synchronization signal provided from the graphic processor and in a panel self refresh (PSR) mode in which a second image is displayed based on a second image signal stored in a frame buffer of the display apparatus and a second synchronization signal generated in the display apparatus, and transmits the second synchronization signal of the PSR mode to the graphic processor when a driving mode of the display apparatus is changed from the PSR mode to the normal mode. The graphic processor is configured to generate the first synchronization signal synchronized with the second synchronization signal.

What is claimed is: 
     
       1. A display system comprising:
 a graphic processor configured to supply a first image signal and a first synchronization signal corresponding to a second frame rate; and 
 a display apparatus configured to: be driven in a normal mode, in which a first image is displayed, during a first period, based on the first image signal and the first synchronization signal provided from the graphic processor; to be driven in a panel self refresh (PSR) mode, in which a second image is displayed, based on a second image signal stored in a frame buffer of the display apparatus and a second synchronization signal, corresponding to a first frame rate, generated in the display apparatus; and to transmit the second synchronization signal of the PSR mode to the graphic processor when a driving mode of the display apparatus is changed from the PSR mode to the normal mode, 
 wherein the graphic processor is configured to generate a third synchronization signal of the normal mode during a second period disposed between a period of the PSR mode and the first period, and corresponding to a frame rate that gradually changes from the first frame rate to the second frame rate. 
 
     
     
       2. The display system of  claim 1 , wherein the display apparatus includes a timing controller configured to transmit the second synchronization signal to the graphic processor. 
     
     
       3. The display system of  claim 1 , wherein the second frame rate is higher than the first frame rate, and the frame rate of the third synchronization signal gradually increases from the first frame rate to the second frame rate. 
     
     
       4. The display system of  claim 1 , wherein the first image signal is transmitted through a main channel, and the first synchronization signal is transmitted through an auxiliary channel. 
     
     
       5. The display system of  claim 4 , wherein the second synchronization signal is transmitted through the main channel or the auxiliary channel. 
     
     
       6. The display system of  claim 1 , wherein the first image signal and the first synchronization signal are transmitted through an interface based on a display port (DP) standard. 
     
     
       7. The display system of  claim 1 , wherein the first image includes a moving image, and the second image includes a static image. 
     
     
       8. The display system of  claim 1 , wherein the second period of the normal mode is a period during which about four or five frames are output. 
     
     
       9. A method of driving a display apparatus comprising:
 driving the display apparatus in a first period of a normal mode, in which a first image is displayed, based on a first image signal and a first synchronization signal corresponding to a second frame rate, the first image signal and the first synchronization signal being provided by a graphic processor; 
 driving the display apparatus in a panel self refresh (PSR) mode in which a second image signal stored in a frame buffer of the display apparatus is displayed based on a second synchronization signal corresponding to a first frame rate and generated in the display apparatus; 
 transmitting the second synchronization signal to the graphic processor when a driving mode of the display apparatus is changed from the PSR mode to the normal mode; and 
 driving the display apparatus during a second period of the normal mode, based on a third synchronization signal corresponding to a frame rate that gradually changes from the first frame rate to the second frame rate, where the second period is disposed between a period of the PSR mode and the first period. 
 
     
     
       10. The method of  claim 9 , wherein the second frame rate is higher than the first frame rate, and the frame rate of the third synchronization signal gradually increases from the first frame rate to the second frame rate. 
     
     
       11. The method of  claim 9 , wherein the first image signal is transmitted through a main channel, and the first synchronization signal is transmitted through an auxiliary channel. 
     
     
       12. The method of  claim 11 , wherein the second synchronization signal is transmitted through the main channel or the auxiliary channel. 
     
     
       13. The method of  claim 11 , wherein the first image signal and the first synchronization signal are transmitted through an interface based a display port (DP) standard. 
     
     
       14. A method of driving a display system including a graphic processor and a display apparatus comprising:
 detecting, using the graphic processor, a driving mode of the display apparatus by detecting a predetermined value of a mode register of the display apparatus; 
 receiving an entry command from the graphic processor using a first receiver of the display apparatus; 
 changing the driving mode from a normal mode, in which a first image is displayed based on a second synchronization signal corresponding to a second frame rate, to a panel self refresh (PSR) mode, in which a second image is displayed, in response to the received entry command; 
 storing a second image signal corresponding to the second image to a buffer in response to a PSR packet received from the graphic processor through the first receiver; 
 receiving an off-command from the graphic processor using the display apparatus; 
 turning off the first receiver connected to the graphic processor through a main channel in response to the received off-command; 
 maintaining a turn-on state of a second receiver of the display apparatus in response to the received off command, the second receiver connected to the graphic processor through an auxiliary channel; 
 generating a first synchronization signal of the PSR mode corresponding to a first frame rate, based on a clock signal generated in the display apparatus; 
 displaying the second image through a display panel of the display apparatus when the first receiver is turned off; and 
 driving the display system during a second period of the normal mode disposed between a period of the PSR mode and a first period of the normal mode, based on a third synchronization signal corresponding to a frame rate that gradually changes from a first frame rate of the PSR mode to a second frame rate of the first period of the normal mode. 
 
     
     
       15. The method of  claim 14 , wherein the first image is a moving image, and the second image is a static image. 
     
     
       16. The method of  claim 14 , wherein the PSR packet is transmitted during a vertical blanking period of a frame of the PSR mode. 
     
     
       17. The method of  claim 14 , further comprising:
 changing the driving mode of the display apparatus from the PSR mode to a normal mode in response to an exit command received from the graphic processor; and 
 turning on the first receiver in response to an on-command received from the graphic processor. 
 
     
     
       18. The method of  claim 17 , further comprising:
 transmitting, using the display apparatus, the first synchronization signal of the PSR mode to the graphic processor; and 
 generating, using the graphic processor, a second synchronization signal of the normal mode based on the first synchronization signal. 
 
     
     
       19. The method of  claim 18 , wherein the second synchronization signal is synchronized with the first synchronization signal. 
     
     
       20. The method of  claim 14 , wherein the second frame rate is higher than the first frame rate, and the frame rate of the third synchronization signal gradually increases from the first frame rate to the second frame rate. 
     
     
       21. A display system comprising:
 a graphic processor configured to supply a first image signal and a first synchronization signal; and 
 a display apparatus configured to: be driven in a normal mode, in which a first image is displayed, during a first period, based on the first image signal and the first synchronization signal provided from the graphic processor; to be driven in a panel self refresh (PSR) mode, in which a second image is displayed, based on a second image signal stored in a frame buffer of the display apparatus and a second synchronization signal generated in the display apparatus; and to transmit the second synchronization signal of the PSR mode to the graphic processor when a driving mode of the display apparatus is changed from the PSR mode to the normal mode, 
 wherein the graphic processor is configured to generate the first synchronization signal in synchronous with the second synchronization signal, 
 wherein a re-synchronization period does not exist between a period of the PSR mode and the first period when the driving mode of the display apparatus is changed from the PSR mode to the normal mode.